Not applicable
1. Backgroundxe2x80x94Field of Invention
The present invention relates to boats of a catamaran type which have a center cabin structure attached to two floating hulls capable of being retracted under said cabin structure to minimize vessel width for maneuvering in crowded marinas, for transporting on a trailer over land, and for minimizing storage space.
2. Backgroundxe2x80x94Description of Prior Art
Catamarans have been used for centuries in the form of two hulls connected in parallel relation for commercial and exploratory purposes. The superior nautical qualities of shallow depth, speed, and stability advantages due to the catamarans high width-to-length ratio thus eliminating the need for large heavy ballasted keels results in the catamarans resistance to capsizing, less weight and greater speed. Catamarans also have a larger living area for their length over trimarans three hulled cousins. Despite these obvious and well known advantages, the catamarans have often had difficulty maneuvering in relatively tight marina docking areas, or packed anchorage areas due to their comparatively massive vessel width. Additionally these wonderfully performing vessels are difficult to transport by trailer over land because of their vessel width. Many boat owners prefer to remove their boats from the water in the winter months to forestall fouling of the boat bottom and thereby greatly reduce the maintenance that otherwise would be necessary if the catamaran were left in the water all year long. Because of the increased difficulty, inconvenience and time lost in the handling, transportation, and storage of conventional catamaran cabin type boats, many would be catamaran owners instead buy a single hulled boat having a large heavy ballasted bottom keel.
To overcome these problems, there have been attempts in the past to design twin-hulled type vessels which collapse into a transportable package, but these designs have been unseaworthy or tent type or cabin structures lacking width stability. Attempts have been made to modify single hulled vessels into trimarans by adding outrigger hulls which are useless for cabin occupancy thus lacking the cabin space that a catamaran with a cabin offers.
U.S. Pat. No. 4,766,830 issued to Kunz discloses a catamaran with a collapsible frame. The reference teaches the use of a tubular frame which is made up of four aft central sub-frame assemblies. The inflatable hulls are then attached to the underside of the sub-frame assemblies. The present invention differs from this invention in that the present invention involves a twin-hulled vessel wherein each hull swing retracts under a central cabin structure by swinging from a row of pivot hinges located close to roof on two opposing sides of said cabin structure. In the same manner or for the same reasons the present invention likewise differs from the following inventions:
U.S. Pat. No. 6,164,238 issued to Scott Alan Stokes,
U.S. Pat. No. 6,029,598 issued to Richard A. Stoll,
U.S. Pat. No. 4,048,685 issued to William A. Gail,
U.S. Pat. No. 5,915,321 issued to Jean-Francois Fountaine,
U.S. Pat. No. 6,695,073 issued to Jerry D. Burkett,
U.S. Pat. No. 5,826,533 issued to James E. Stangroom and John G. Clancy,
U.S. Pat. No. 5,522,339 issued to Charles W. Pelly,
U.S. Pat. No. 5,174,232 issued to Graeme J. Broddy,
U.S. Pat. No. 5,277,142 issued to Dennis P. Connor,
U.S. Pat. No. 5,042,411 issued to Ronald G. Krolczyk,
U.S. Pat. No. 5,184,565 issued to Keith R. Matthews,
U.S. Pat. No. 4,993,340 issued to Orlyn G. Pepper,
U.S. Pat. No. 4,856,446 issued to Yves Herard,
U.S. Pat. No. 4,406,239 issued to Klaus Enzmann,
U.S. Pat. No. 3,981,259 issued to William H. Harper,
U.S. Pat. No. 3,203,014 issued to Clifford H. Krueger.
The present invention differs from all above listed inventions in that the present invention involves a multi-hulled vessel wherein each said hull swing retracts under said central cabin structure by swinging from a row of said pivot hinges located close to roof on two opposing sides of said cabin structure. Moreover the present invention involves inboard side hull rollers or sliders that are guided to roll or slide on a system of parallel spaced apart out ward extending tracks or channels.
The present invention relates to a retractable multi-hulled vessel which is simple to vary vessel width of watercraft yet be strong and light. More particularly, it is an object of the present invention to with ease be able to reduce vessel width for trailer towing over land or maneuvering in crowded waters as well as to widen vessel width for stability and added usable space. An additional object of the present invention is to have each hull space able to be accessed from inside the main living area when hulls are extended as well as have the main living area livable when hulls are retracted in crowded waters.
The present invention provides a catamaran boat which goes far to overcome the problems of prior art. A retractable multi-hulled watercraft according to this present invention has a central cabin structure with a roof, some walls, and a floor structure which has a underside track system. This cabin structure is carried above water by two or more retractable hulls whether hulls are extended or retracted. Each of these said hulls has a upward extending hull wall with top end pivot hinged close to roof on two opposing sides of said cabin structure and bottom end either hinged or securely fastened to outboard side of each said hulls in such a manner as to enable said hulls to swing retract under said cabin structure. The inboard sides of each said hulls has a roller (or slider) system that are guided to roll (or slide) on said track system that is attached to the bottom of said cabin structure wherein roller (or slider) travel is limited by a outer surrounding frame attached to both ends of each track. Vessel width may be easily varied by uniformly rotating a pair of dual threaded shafts, each having opposite threaded brackets which are attached to inboard sides on forward and aft ends of each said hulls in such a manner that rotating said shafts causes said hulls to either spread apart or move closer together.
When said hulls are extended (spread apart), the space inside each hull becomes usable and accessible from the inside of said cabin structure. The resulting wide vessel width resists capsizing thereby eliminating any need for a large heavily ballasted bottom keel. Hence more living space for its length, less weight resulting in faster speed, plus the ability to travel in shallow waters.
When said hulls are retracted (close together), results in almost half the vessel width while still having livable cabin space and being able to more easily maneuver in crowded waters. Furthermore the reduced vessel width allows the catamaran to be transported over land by trailer. An alternative embodiment discloses a catamaran having a wheel/axle assembly mounted on a struts/cylinders assembly able to have a raised (stowed) position located between two pairs of previously described retractable hulls with hull walls.
Thus the present invention overcomes many of the problems of prior art mono-hull boats, trimaran boats, and catamaran boats. Other advantages, objects, and details of the present invention will become apparent as the following detailed disclosure proceeds.